Various methods for representing indoor and outdoor environments using digital information have been introduced since 100 years ago. A camera is introduced in order to obtain image information of an environment and various range finders are introduced in order to obtain depth information of the environment. Further, recently, a sensor system which simultaneously obtains an image and a depth value obtained through JUMP by Google or Project Beyond by Samsung to produce a 3D image and provides the 3D image to a user through a head mount display (HMD) is also launched. However, since the above-mentioned systems may obtain data in only one location, there is a limitation that only information on a specific field of view in a specific pose (a location and an angle in a two-dimensional or a three-dimensional space) may be recorded.
In order to overcome the above limitation, several images and depths may be obtained at narrow intervals. For example, in a street view map service of an Internet portal, images are photographed at narrow intervals and the same implementation may be achieved also in JUMP or Project Beyond.
However, the related art may have a limitation that when a virtual user is located in a pose where no image is obtained, a 3D image corresponding to the location may not be generated. According to the related art, when the virtual user is located in a pose on a virtual 3D space where no image is obtained, images obtained in poses before and after the pose are mixed to display a 3D image. Further, an image obtained in a next pose is used to display a 3D image as the user moves. Therefore, according to the related art, the user may feel that the image is unnatural.
In order to overcome the above problem, an image and a depth value are obtained from a plurality of continuous poses so that a natural 3D image may be displayed as the user moves. However, in this case, there is a limitation that only when the user moves along the same route as the route where the image and the depth value are obtained, the natural 3D image may be displayed. In other words, the user cannot move out of the route from which the image is obtained so that there is a limitation that the method may be used only to produce contents for experiencing a ride such as a roller coaster.
Further, when the image is photographed by an omnidirectional camera, a method which moves a field of view to the left and right with respect to a center point of the corresponding image to produce a binocular image and display the binocular image through a head mount display (HMD) device is used. However, according to this method, even though the photographed image may rotate at 360 degrees in accordance with a characteristic of the omnidirectional camera to be watched as a 3D image, there is a limitation that the image cannot be watched out of the photographing route.
As described above, the related art has a problem in that in the indoor and outdoor environment, a realistic 3D image in accordance with arbitrary movement and arbitrary rotation of the user cannot be provided.